Variable-frequency motor drive systems control motor speed and torque of an electric motor. Such drive systems are widely used in power electronics applications. The drive system implemented depends on characteristics of the application, such as sampling frequency, load requirements, and speed requirements. One technique to control the torque of electric motor drive systems is direct torque control (DTC), which uses a closed-loop control scheme. In contrast to field oriented control (FOC), DTC directly controls the electromagnetic torque and stator flux linkage. In a discrete or digital system, hysteresis thresholds and sampling periods affect the performance of the DTC system.